The present invention relates to novel polymerizable cationic monomers and to homopolymers and copolymers thereof. The novel polymerizable monomers of this invention are polymerizable esters, the acyl group of which is that of certain ethylenically unsaturated carboxylic acids and the alcoholic component of which is that of an alcohol containing two or more cationic groups. All of the cationic groups may be quaternary ammonium groups or the terminal cationic group may be a tertiary amino group.
A number of polymerizable cationic monomers, particularly polymerizable cationic acrylic ester monomers, are well known in the art and are finding substantial commercial use for the production of polymers having cationic properties. Such polymerizable cationic monomers are used for the production of homopolymers and more especially for the production of copolymers with such monomers as acrylic esters (e.g., ethyl acrylate or methyl methacrylate), styrene, vinyl acetate, vinyl chloride, acrylamide and acrylonitrile. As examples of commercially available cationic acrylate and methacrylate monomers may be mentioned dimethylaminoethyl methacrylate CH.sub.2 =C(CH.sub.3) COO--CH.sub.2 CH.sub.2 N(CH.sub.3).sub.2 and its quaternization products such as its quaternization product with dimethyl sulfate which can be represented by the formula: ##STR4## or its quaternization product with methyl chloride which can be represented by the formula ##STR5## Another such cationic arcylic ester monomer which is commercially available is the quaternization product of 1-chloro-2-hydroxypropyl methacrylate and trimethyl amine, made by the reaction of methacrylic acid, epichlorohydrin and trimethyl amine and represented by the formula ##STR6##
The foregoing commercially available polymerizable cationic acrylic ester monomers are characterized by the presence of a single tertiary amino group or a single quaternary ammonium group in the molecule. Consequently, particularly in the production of copolymers, where a high degree of cationic functionality is desired in the polymer backbone, it is necessary to use a high proportion of these cationic monomers to its comonomer. While such high relative proportion of these cationic monomers is desirable to increase the cationic functionality of the polymer backbone, it may at the same time dilute or adversely affect other desirable properties contributed by the comonomer to the resulting copolymer.